Size optimization for high frequency quartz resonator using finite element vibration analysis

In this study, size optimization for a high frequency AT-cut quartz resonator using finite element vibration analysis is presented. The objective resonator is a high frequency fundamental resonator with one-sided electrodes structure, which has high Q value and low resistance compared to the widely used overtone resonators. The one-sided electrodes structure was designed to obtain effective energy trapping and suppress inharmonic overtone (IO) mode. A convenient 2-D model using rectangular element was established to well reconcile calculation time with accuracy. A frequency mode chart describing the relationship between vibration coupling and size of quart plate was achieved. Vibration coupling and energy trapping effect were examined for different sizes of electrodes. COMSOL MULTIPHYSICS™ was adopted as a FEM analysis tool and the simulation results confirmed the effectiveness of this work.